According to prior art, see e.g. DE 196 15 702, micro liter centrifuges are known, using which samples, which are held in a rotor driven by a motor, can be centrifuged. Below this rotor, air is sucked in and guided to the rotor outer wall so that the rotor outer wall and the samples contained in the rotor are cooled by the flow of the air. After a heat exchange, which thus takes place with the rotor surface and/or the samples located in the rotor, the air escapes from an outlet opening, which is arranged above the rotor.
The outlet opening is provided with a wall, on which a part of the air particles can impinge frontally. This results in front of such a wall in a whirl zone and/or a zone having a no longer linearly directed flow and relatively high pressure in comparison with a zone which is at a further distance from the wall. This whirl zone can cover a relatively large area, as a result of which the actually effective outlet opening, along which the cold air can escape from the centrifuge, is reduced.
In a region above the rotor and in the vicinity of the wall on which the air particles impinge, a displacement body is additionally arranged according to prior art, wherein said displacement body is supposed to prevent air particles, which are on their way to the outlet opening from being dragged along again by the rotor flow into an air channel, which surrounds the rotor. Due to the displacement body, the area of the whirl zone in the transmission region between the air channel and the wall of the outlet opening is increased. This can sometimes lead to a reduction in the heat dissipation from the centrifuge.
Against this background, the object of the invention is to optimize the air transport around the rotor and out of the centrifuge in the generic centrifuge with the best possible heat dissipation.